Paroxysmal Nocturnal Haemoglobinuria (PNH)
- Dr Cleona Duggan Consultant Haematologist - Cork University Hospital
Mantle cell lymphoma (MCL) is a B cell malignancy that has long been considered to be incurable. Recent advances in therapies has led to an increase in the number of patients that are classed as being in complete remission. However, relapse in patients is still of major concern, and low levels of pathological cells have shown to still be a significant cause for the disease to relapse. For this reason, methods of determining residual disease are being highly developed. The gold standard method that is currently used is PCR. Flow cytometry has previously been shown to not reach the sensitivity levels of PCR. Development of multicolour flow cytometry (MCF) methods have shown this to no longer be true and they can reach the same sensitivity as PCR. This study aimed to validate an eight colour single tube MCF assay. The study showed that the assay and sequential gating strategy, developed with Facs Diva software, was capable of identifying pathological populations of cells in samples with very low disease burden, and reached a robust sensitivity of 0.024%.
Increased Mean Corpuscular Haemoglobin Concentration (MCHC) >36.5g/dL can occur because of analytical interference or red cell disease. The aim of this study was to establish if optical red cell parameters RBC-O and HB-O from the Sysmex XN RET channel could be used to overcome raised MCHC’s caused by analytical interference. 299 unknown patient samples with MCHC >36.5g/dl were measured through the Sysmex XN RET channel.
RBC-O provided an accurate red cell count in cold agglutinin samples without the need for sample warming. In samples that had optical interference, HB-O was shown to provide an accurate HB count. Red cell disease group could be separated from all groups using an RBC score based on the reticulocyte count. An algorithm was determined using the optical parameters for routine use for samples with raised MCHC >36.5g/dL.
Objective: To assess the prevalence and determinants of haematinic deficiency (lack of B12 folate or iron) and macrocytosis in blood from a national population-based study of middle-aged and older adults.
Methods: A cross-sectional study involving 1,207 aged ≥45 years, recruited from a sub-study of the Irish National Survey of Lifestyle Attitudes and Nutrition (SLÁN 2007). Participants completed a health and lifestyle questionnaire and a standard food frequency questionnaire. Non-fasting blood samples were obtained for measurement of full blood count and expert morphological assessment, serum ferritin, soluble transferrin receptor assay (sTfR), B12, folate and coeliac antibodies. Blood samples were also assayed for thyroid function (T4, TSH), liver function, aminotransferase (AST) and gamma-glutamyl transferase (GGT).
Results: The overall prevalence (95% C.I.) of anaemia (Hb <13.5g/dl men and <11.3g/dl women) was 4.6% (2.9%-6.4%) in men and 1.0% (0.2% -1.9%) in women. Iron deficiency (ferritin <17ng/ml men and <11ng/ml women) was detected in 6.3% of participants (3.7% in males and 8.7% in females, p<0.001). Based on both low ferritin and raised sTfR (>21nmol/ml) only 2.3% were iron deficient. 3.0% and 2.7% were found to have low levels of serum folate (<2.3ng/ml) and serum B12 (<120ng/l) respectively. Clinically significant macrocytosis (MCV>99fl) was detected in 8.4% of subjects. Strong, significant and independent associations with macrocytosis were observed for lower social status, current smoking status, moderate to heavy alcohol intake, elevated GGT levels, deficiency of folate and vitamin B12, hypothyroidism and coeliac disease. The population attributable fraction (PAF) for macrocytosis associated with elevated GGT (25.0%) and smoking (24.6%) was higher than for excess alcohol intake (6.3%), folate deficiency (10.5%) or vitamin B12 (3.4%).
The extended reticulocyte parameters (ERPs) include: MCVr, MCHr and CHCr. They have a number of established clinical uses, including the diagnosis of certain anaemia’s and monitoring of therapy.
The aim of this study was to evaluate the ERPs on the Cell-Dyn Sapphire analyser and determine their use in the investigation of iron deficiency anaemia.
A reference range was developed for the ERPs and their specificity for diagnosing iron deficiency was assessed. A statistically significant difference was found for each extended reticulocyte parameter between iron deficient and non iron deficient patients. However none of the extended reticulocyte parameters were found to be highly specific for iron deficiency. At lower ferritin levels (<10µg/L), the specificity of the extended reticulocyte parameters for iron deficiency increased.
These results suggest that the ERPs are not useful to diagnose all cases of iron deficiency, but appear to be more useful in severe cases. The ERPs may be useful in diagnosing iron deficiency where the ferritin is falsely elevated and this should be investigated in future studies.
Platelets are anucleate cell fragments whose primary role is in haemostasis and the maintenance of vascular integrity. When activated, platelets release a multitude of proteins from their cytoplasm and preformed granules, known as the platelet proteome. Mass spectrometry studies have identified hundreds of proteins in this platelet releasate. The presence of the protein antithrombin in and its interaction with platelets is not well characterised. This project was designed to determine if antithrombin is part of the platelet proteome and to observe the effect which antithrombin has on platelets. This was achieved by using techniques such as a western blot, immunofluorescence, adhesion assays and flow cytometry.
Full identification of the proteins stored in and released by platelets when activated is important so that the role of these proteins can be determined. It is also crucial to develop a deeper knowledge of how plasma proteins interact with platelets so a better understanding of how platelets contribute to homeostasis can be made.